South Africa and Munster second row RG Snyman will spend time on the sidelines after he had ruptured his cruciate ligament.
The 26-year-old sustained the blow while playing for his club Munster in the recently concluded United Rugby Championship game against Scarlets where he was forced off the field in the 60th minute.
Snyman, who was part of South Africa's successful World Cup campaign already suffered a cruciate injury during his debut with Munster last year and suffered another injury later in the season.
He will now consult a specialist on a possible surgery to address the issue.
“We are all hugely disappointed for RG,” said Munster boss Johann van Graan.
“After doing everything that was asked of him and working so hard to get back into great shape everyone feels for him right now.
“While this is a setback, we know RG is young and resilient given everything he has gone through in the last year so there is a strong sense of perspective here.
“We have seen what other world class players have done in this position before and they have come back to reach the successful heights of their careers and I would expect no different for someone of RG’s class and standing.”